Means for adjustable suspending power tools over table tops



Dec. 14, 1954 w. L DAVIS MEANS FOR ADJUSTABLY susmmams POWER TOOLS OVERTABLE TOPS Filed Oct. 13, 195i 2 Sheet-Sheet 1 I N VEN T013. Wham L-QausBY X A TTOR/Vf) Dec. 14, 1954 w. I. DAVIS 2,696,851

MEANS FOR ADJUSTABLY SUSPENDING POWER TOOLS OVER TABLE TOPS 2Sheets-Sheet 2 Filed Oct. 13, 1951 INVENTOR:

X A TTO/PNEY United States Patent MEANS FOR ADJUSTABLY SUSPENDING POWERTOOLS OVER TABLE TOPS William L. Davis, Fort Bragg, Calif.

Application October 13, 1951, Serial No. 251,233

6 Claims. (Cl. 143-6) The present invention relates to suspension meansfor a power tool, and has particular reference to suspension means for arotary power saw over a table top with freedom of various adjustments.

More particularly it is proposed to provide a yoke frame adapted formounting on a table top having a shaft supported transversely in thecenter thereof, with means for adjusting the shaft support with respectto the frame and the shaft with respect to the support.

It is further proposed to use the end of the shaft for supporting thevertical member, with means for adjusting the vertical member verticallyand angularly with respect to the table top and means for locking thesaid member in adjusted position.

Another object of my invention is to provide a gauge readable againstthe end of the shaft for determining the height of a suspended tool withrespect to the table top and the angularity of the tool with respect toa straight edge on the table top.

A still further object of my invention is to use the said member as asupport for a horizontally presented rail which partakes of theadjustments of the said member.

It is further proposed to provide a carriage on said rail, the carriagehaving the tool suspended therefrom and being free to ride in the railfor sawing operations.

It is additionally contemplated to provide means whereby the rail may betilted transversely with respect to the supporting member to bring thesaw into a desired angularity with respect to the plane of the table topto cut through the wood or other work at a desired angle, and to provideaccurate means for effecting the adjustments and means for locking therail in adjusted position.

Further objects and advantages of my invention will appear as thespecification proceeds.

The preferred form of my invention is illustrated in the accompanyingdrawing, forming part of this application, in which:

Figure 1 shows an end view of my suspension means, looking at it fromthe rear of the table;

Figure 2, a side view of the same;

Figure 3, a plan view of the same;

Figure 4, an enlarged detail section taken along line 4--4 of Figure 2;

Figure 5, a detail view in plan of a straight-edge used in connectionwith my invention; and

Figure 6, a side view of the same.

While I have shown only the preferred form of the invention, it shouldbe understood that various changes or modifications may be made withinthe scope of the claims attached hereto without departing from thespirit of the invention.

Referring to the drawing in detail, my invention comprises in itsprincipal features, a yoke-shaped frame 1 adapted for mounting upon atable top 2, a cross 3 mounted in the frame, a shaft 4 slidabletransversely in the cross, a worm 5 suspended from the shaft, a rail 6carried by the worm, a carriage 7 slidable in the rail and a toolsupport 8 suspended from the carriage.

The frame 1 is here shown as being arcuate and comprising two standardshaving bottom flanges 9 adapted for fastening to a table top and curvingtoward one another to terminate in alined horizontal stretches joinedcentrally by the cross 3, the latter being held to the ends of thestandards by means of nuts 10, which allows of a certain amount ofadjustment of the cross with respect to'the standards, by backing one ofthe nuts and advancing the other.

The cross-arms of the cross have the shaft 4 slidably mounted therein,the shaft being held against turning movement by means of a set screw 11engaging in a lengthwise groove 12 of the shaft, which latter set-screwmay also be used to lock the shaft against endwise motion.

The end of the shaft is flattened at the top and the bottom to presentflat top and bottom surfaces 13 and 14 and is formed with a centralvertical hole in which the worm 5 is slidably received, the worm beinglocked in any desired position by means of two nuts 15 and 16, the upperone of which has a handle 17 projecting therefrom. The worm may beraised and lowered by backing one of the nuts and advancing the oppositenut and may be locked in adjusted position by tightening the nuts uponthe shaft. It will be noted that as long as the nuts are not tightened,the worm is free to revolve in the shaft, without changing theelevation.

The bottom end of the worm carries a head 18 which is split horizontallyto present two sections 19 and 20, the section 19 being fixed to theworm, and the section 20 being hinged to the section 19, as at 21.

The lower section has the rail 6 permanently and fixedly secured uponthe lower face thereof. The rail is disposed horizontally and preferablycomprises two channels' 22 arranged back to back in spaced relation bysuitable spacing members indicated at 23. The confronting faces of thechannels are formed with upper and lower tracks 24, and a four-wheelcarriage 25 is movable between the tracks, the carriage comprising apair of spaced axles 26 and bearing wheels adapted to ride between thetracks.

The wheels are made of sufiicient size to contact both upper and lowertracks, so as to prevent tilting longitudinally and to come close to thechannels to guard against lateral tilting with respect to the channels.The carriage also includes the supporting member 8 suspended from theaxles which latter has the tool housing 27 rigidly secured thereto.

The supporting member preferably is in the form of a flat plate set onedge and of sufficient width to be in sliding contact with the sides ofthe lower tracks 24 so that the latter may serve to steady the carriagewhen the rail as a Whole is tilted on the hinge 21. The supporting plateis not intended to extend into the space between the upper tracks,because the carriage is supposed to carry the main part of the load atany desired anguarity.

The lower section 20 is held to the upper section by means of a sideplate 28 secured upon the upper section by means of a screw 29 and uponthe lower section by means of a screw 30. As long as both screws arescrewed tightly, the sections are rigidly connected. But the uppersection is formed with a slot 31, the walls of which engage over thescrew 29, and if the two screws are loosened, the slot walls ride alongthe screw 29 and allow the lower section to drop, on its hinge, to anydesired angularity, to be held again in adjusted position by tighteningof the screws. Notches 32 may be provided in the upper edge of the plate28 for reading against the upper surface of the upper section toindicate the angle of the lower section, the upper edge of the platebeing preferably made cam-shaped, as shown.

The outer edge of the upper section 19 of the worm head has a gauge 33projecting upwardly therefrom to read against the upper surface of theshaft 4. When the top of the gauge is on a level with the said uppersurface, this may be made an indication that the cutting edge of the sawshown at 34 is disposed immediately adjacent the top of the table. Asthe worm is raised, the scale on the gauge indicates the height of thesaw above the table surface. The gauge 33 is pivoted to the section 19as at 33', so that it may be swung downward into an out-of-the-wayposition.

The upper face 13 of the shaft is also calibrated, as at 35, to indicatethe angle of the rail with respect to the table edge or a straight edgedisposed on the table, these calibrations being also readable againstthe gauge 33.

A suitable auxiliary means may be provided for accurately adjusting thelower head section 20 to a desired angulari-ty, in the form of aturnbuckle 36 securable to the rail, as at 37, and to a bracket 38mounted upon one of the standards with freedom of vertical and angular.adjustabilit-y, the bracket being held in adjusted posh tion by the setscrew 39.

A suitable straight-edge particularly adapted for use in connection withmy invention is shown as comprising a T-square 4 of a length slightly inexcess of the width of the table top and having a head 4-1 at one endand a link 42 at the other end, the link being adapted to be drawn uponthe table edge opposite the head by means of a wire 43 and a lever 44which firmly holds the T- ,square in rectangular position when the leverand the wire reach dead-center position.

The advantages of my suspension means will be apparent from theforegoing description. The suspension means may be perfectly balancedwith respect to the main frame 1 by adjustment of the nuts 10. The shaft4 is adjustable cross-wise of the main frame to bring the worm 5relatively close to the main frame or a considerable distance away fromthe frame. It is even possible to project the worm 5 to a positionoutside the table top, if it is desired to work on a piece of wood whichis more conveniently mounted on some other support.

The height of the saw blade may be readily and accurately adjusted bysuitable operation of the nuts 15 and 16, and while this adjustment isbeing made the saw blade may swing into adesired angular position withrespect to the straight-edge, both the height and angular position beingreadily discernible by reading the gauge 33 against the top face 13 ofthe shaft and the angular scale thereon.

The angle of the saw blade with respect to the table top may be readilyadjusted by operation of the plate 28 and theexact angle ascertained byreading the notches on the plate against the head section 19.

When the rail is adjusted to angular position, the four- Wheel carriagebearing against both upper and lower tracks will maintain the tool inthe plane to which it has been adjusted, without interfering with theoperation of the saw.

I claim:

1. In combination, a shaft, means for horiztonally supporting the sameover a table top, a worm slidable and revolvable in the shaft, a pair ofnuts on the worm and cooperable with the shaft for locking the worm tothe shaft, a head at .the lower end of the worm split horizontally topresent an upper and a lower section, a hinged connection between thesections allowing the lower section to swing downwardly, means forlocking the lower section in adjusted position, and a guide rail securedupon the lower section.

2. In combination, a shaft, means for horizontally supporting the sameover a table top, a worm slidable and revolvable in the shaft, a pair ofnuts on the worm and cooperable with the shaft for locking the worm tothe shaft, a head at the lower end of the worm split horizontally topresent an upper and a lower section, a hinged connection between thesections allowing the lower section to swing downwardly, means forlocking the lower section in adjusted position, and a guide rail securedupon the lower section, the guide rail having a carriage .movablethereon, and the carriage having a tool housing suspended therefrom.

3. In combination, a shaft, means for horizontally supporting the sameover a table top, a vertical member carried by said shaft, a head at thelower end of the member split horizontally to present an upper and alower section, a hinged connection between the sections allowing thelower section to swing downwardly, means for locking the lower sectionin adjusted position, and a guide rail secured upon the lower section soas to present a track clear from end to .end.

4. In combination, a shaft, means for horizontally supporting the sameover a table top, a vertical member carried by the shaft, a head at thelower end of the member split horizontally to present an upper and alower section, a hinged connection between the sections allowing thelower section to swing downwardly, means for locking the lower sectionin adjusted position, and a guide rail secured upon the lower section soas to present a track clear from end to end, the locking means comprsing a plate positioned adjacent the two sections and screws forsecuring the plate upon the two sections, and the plate having a slotadapted for riding on one of the screws when the screws are loosened.

5. In combination, a yoke adapted for mounting on a table top and havingspaced legs and a bridging member connecting the upper ends thereof, ashaft mounted horizontally in the bridging member and transversely tothe latter and having an end projecting beyond the yoke, a membersuspended from the said end, a guide rail supported horizontal-1y by thesaid member and having an end extending through the yoke, and a carriageslidably supported by the guide rail and operable within the confines ofthe yoke, the guide rail being hinged to .the suspended member forangular adjustment and having means for locking the same uponadjustment.

6. In combination, a yoke adapted for mounting on a table top and havingspaced legs and a bridging member connecting the upper ends thereof, ashaft mounted horizontally in the bridging member and transversely tothe latter and having an end projecting beyond the yoke, a membersuspended from the said end, a guide rail supported horizontally by thesaid member and having an end extending through the yoke, and a carriageslidably supported by the guide rail and operable within the confines ofthe yoke, the guide rail being hinged to the suspended member forangular adjustment and having means for locking the same uponadjustment, and the guide rail and the carriage having closely fittingcooperative means for goldinlg the carriage against tilting motion withrespect to t e rai References Cited in the file of this patent UNITEDSTATES PATENTS

